Light emitting diode (LED) will have development in liquid crystal display (LCD) backlight. Nevertheless, the point source of LED is not suitable for large size panel. Therefore, this research will change the package which is bullet type and design gapless dual-curvature micro lens (GDML). Using the optics software TracePro is simulation luminance to compare of hexagon, triangular and dual-curvature micro lens, and fabrication of the better size. We can get metal model using micro-electro-mechanical systems (MEMS) technology after electroforming and hot embossing. The micro lens is formed by UV cure in metal model. It has different curvature and fill factor 100%. The advantage of electroforming is can manufacture a lot of product fast with high performance. The shrinkage rate is less than 0.5%. The collocation package of micro lens and LED chip can improve intensity and uniformity.

In this dissertation work, a constant temperature embossing process was developed and investigated. By softening and crystallizing a supercooled polymer at the same temperature, the embossing and solidification stages can be carried out isothermally without thermal cycling. The new process was demonstrated for replicating rectangular trenches with different aspect ratio for two different polymers PET and PEEK. The raw materials were characterized for their thermal and rheological properties to determine the processing parameters. The polymers were also characterized by a modified tensile testing apparatus to determine the tensile properties of the film during embossing. The processing parameters including embossing temperature, embossing pressure and embossing time were varied based on the material properties and optimized. A semi-empirical model was established to correlate the crystallizing kinetics of the materials to the change in rheological properties during embossing. The model was used as a tool to predict the rheological properties of the polymer at conditions where experimental determination is difficult. Finally, embossing simulations with the semi-empirical rheological model were conducted to study the unique process dynamics of constant-temperature embossing and verify some experimental findings. Different cases of constant-temperature embossing involving low to high rates of crystallization were simulated and compared with the conventional embossing process. Based on the experimental and simulation results, processing strategies for constant-temperature embossing were devised.

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This experiment produces a new flexible heat pipe, and further tests and explores its characteristics and performance. The heat pipe is made of silicone rubber, a kind of polymer material, and was molded by hot embossing. Characteristics of this material include good bending resistance, lightness, and good resistance to high temperature. Furthermore, copper sheets connected with silicone were placed at the evaporator section and condenser section to enhance heat transfer effects. DI water in the pipe was used as the working medium, and two-layer 250 mesh copper nets were used as a wick to strengthen the heat pipe¡¦s capillary effects. The researcher set the vacuum degree at 0.0658 atm to test the pipe¡¦s performances at different powers. Key findings include an optimum filling ratio of 40%, and a largest heat flux of 11.75 W/cm2 during the proficiency test. In addition to the proficiency test . The influence of different angles of bends (0 ~ -90¢X) on the pipe¡¦s heat transfer performance was also tested and based on heat thermal resistance obtained, found that the best bended angle of the flexible heat pipe was -15¢X, and thermal resistance will increase with the angle(-30 ~ -90¢X). The experiment proves a small angle bend that is helpful for the working medium to flow back to the evaporator section, but the heat transfer performance would shrink because the wick could not affix to the inner wall of the pipe if the angle is too large. This work shows the proper combination of pipe parameters will significantly improve heat transfer performance.

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<p>In later years polymer replication techniques have become a frequently employed fabrication method for microfluidic and micro-optical devices. This thesis describes applications and further developments of microstructures replicated in polymer materials. </p><p>A novel method for homogenous amplified single-molecule detection utilizing a microfluidic readout format is presented. The method enables enumeration of single biomolecules by transforming specific molecular recognition events at nanometer dimensions to micrometer-sized DNA macromolecules. This transformation process is mediated by target specific padlock probe ligation, followed by rolling circle amplification (RCA) resulting in the creation of one rolling circle product (RCP) for each recognized target. Throughout this transformation the discrete nature of the molecular population is preserved. By hybridizing a fluorescence-labeled DNA detection oligonucleotide to each repeated sequence of the RCP, a confined cluster of fluorophores is generated, which makes optical detection and quantification possible. Spectral multiplexing is also possible since the spectral profile of each RCP can be analyzed separately. The microfluidic data acquisition process is characterized in detail and conditions that allow for quantification limited only by Poisson sampling statistics is established. The molecular characteristics of RCPs in solution are also investigated.</p><p>Furthermore a novel thermoplastic microfluidic platform is described. The platform allows for observation of the microchannels using high magnification optics and also offers the possibility of on-chip cell culture and the integration of mechanical actuators.</p><p>A novel fabrication process for the integration of polymer micro-optical elements on silicon is presented. The process is used for fabrication of a micro-optical system consisting of a laser and a movable microlens making beam steering possible. Such a micro-scanning system could potentially be used for miniaturized biochemical analysis.</p>

In later years polymer replication techniques have become a frequently employed fabrication method for microfluidic and micro-optical devices. This thesis describes applications and further developments of microstructures replicated in polymer materials. A novel method for homogenous amplified single-molecule detection utilizing a microfluidic readout format is presented. The method enables enumeration of single biomolecules by transforming specific molecular recognition events at nanometer dimensions to micrometer-sized DNA macromolecules. This transformation process is mediated by target specific padlock probe ligation, followed by rolling circle amplification (RCA) resulting in the creation of one rolling circle product (RCP) for each recognized target. Throughout this transformation the discrete nature of the molecular population is preserved. By hybridizing a fluorescence-labeled DNA detection oligonucleotide to each repeated sequence of the RCP, a confined cluster of fluorophores is generated, which makes optical detection and quantification possible. Spectral multiplexing is also possible since the spectral profile of each RCP can be analyzed separately. The microfluidic data acquisition process is characterized in detail and conditions that allow for quantification limited only by Poisson sampling statistics is established. The molecular characteristics of RCPs in solution are also investigated. Furthermore a novel thermoplastic microfluidic platform is described. The platform allows for observation of the microchannels using high magnification optics and also offers the possibility of on-chip cell culture and the integration of mechanical actuators. A novel fabrication process for the integration of polymer micro-optical elements on silicon is presented. The process is used for fabrication of a micro-optical system consisting of a laser and a movable microlens making beam steering possible. Such a micro-scanning system could potentially be used for miniaturized biochemical analysis.

Brightness enhancement film (BEF) has been manufactured in foreign factories for backlight module of liquid crystal display (LCD), then it only have some interior factories to put in exploitation. Because of this, the study presents a precision machining and new step-imprint hot embossing process to fabricate pyramid-shaped microlens array. First, a tungsten (W) steel material is manufactured by precision machining. The dimension of a pyramid-shaped microlens on the W steel are about 300 £gm in the base line of three side, 222 £gm in bevel edge of three side, 139 £gm in height of bottom to top, 180 £gm in pitch of the left and right sides between two pyramid-shaped microlens tips, and 85 degree in top angle of three bevel. The W steel mold is used as the first mold. Second, the pyramid peaks of first mold pattern are transferred on bulk metallic glass (BMG) using step-imprint hot embossing method with position adjustable mechanism to form a smaller concave pyramid-shaped microlens array, it can avoid arc radius of cutting tools which is used as the second mold. Another the pyramid peaks are transferred on PMMA (Polymethylmethacrylate) for concave pyramid-shaped microlens array of optical film in the hot embossing system. Finally, the second mold is fabricated to emboss convex pyramid-shaped microlens array of optical film on PMMA. The foregoing method is provided for backlight module of optical films process.

The goal of this research is to develop an integrated polymer embossing module, with which difficult-to-emboss polymer microstructures and microparts can be fabricated in a cost-effective manner. In particular, the research addresses three major limitations of the hot embossing process, namely, long cycle time, difficulty in producing shell patterns, and difficulty in building up a high embossing pressure on thick substrates. To overcome these limitations, three new technical approaches two-station embossing, rubber-assisted embossing, and through-thickness embossing were developed and investigated. Fundamental understanding of these new embossing techniques were achieved through extensive experimental and theoretical studies involving parametric experiments, rheological characterization, surface investigation, mathematical modeling, and computer simulation.

<p>The interest for miniaturisation in chemical and biological analysis has increased in recent years. In this work, the design, fabrication and characterisation of tools for microanalysis have been studied. The focus is set on polymer microchips for applications in chemical analysis. The work consists of three parts: design and fabrication of paraffin microactuators, design and fabrication of polymer microchips as interfaces in electrospray ionisation mass spectrometry (ESI-MS), and characterisation of conducting films for fused silica capillaries as interfaces in ESI-MS.</p><p>The principle of the paraffin actuators is based on the volume increase resulting from paraffin melting. Paraffin expansion is utilised to cause membrane deflection. The first plastic microactuator using paraffin as the actuator material was successfully demonstrated.</p><p>The microchips as interfaces in ESI-MS have been designed with the objective that the interface should be as much a part of the microchip as possible, and as to as large extent as possible, be fabricated in the same step as the microchannels. Sheathless electrospray from microchips was demonstrated for the first time. In addition a simplified fabrication process for ESI-MS interfaces in poly(dimethyl siloxane) (PDMS) was developed.</p><p>The degradation of conductive coatings for sheathless ESI-MS on fused silica capillaries was studied. It was shown that electrochemical experiments could successfully be used to simulate the electrospray conditions and predict the failure of different gold coatings.</p><p>It was concluded that a common issue in the fabrication of thermoplastic microchips is the crucial sealing of microchannels and cavities. From this point of view, PDMS is a more advantageous material in microfluidics.</p>